Lithography technology plays an extremely important role in a process to advance the miniaturization of semiconductor devices. In recent years, along with the high integration of LSIs, the circuit line width required for semiconductor devices has been shortened year by year. Since electron ray (electron beam) drawing technology has inherently excellent resolution, the electron ray has been used to draw a mask pattern on a mask blank.
A drawing apparatus using a multi-electron beam (multibeam) can greatly improve the throughput as compared with a case of drawing with one electron beam. In such a multibeam drawing apparatus, for example, an electron beam emitted from an electron gun is passed through a shaping aperture having a plurality of holes to form a multibeam. Each electron beam constituting the formed multibeam is subjected to blanking control by a blanking aperture array. The electron beam deflected by the blanking aperture array is blocked (blanked), and a sample such as a mask blank is irradiated with the undeflected electron beam.
The blanking aperture array is provided with through holes through which the respective electron beams pass. And, a pair of electrodes for deflecting the electron beam is provided around each of the through holes. The manufacture of the blanking aperture array adopts a method in which each of the through holes and each of the pairs of electrodes described above are formed on, for example, a silicon (Si) substrate by using semiconductor manufacturing technology.
Herein, when a dicing tape is attached to the upper face of the through holes and then the dicing tape is peeled off in order to process the blanking aperture array or the like, there has been a problem that an adhesive of the dicing tape enters the through holes and remains inside.